DRAFT REPORT FOR FOR CONSULTATION

1
2
3
4

5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30

ICRP ref 4838-8963-9177
July 21, 2011

Annals of the ICRPICRP PUBLICATION XXXRadiological Protection in Geological
Disposal of Long-Lived Solid
Radioactive Waste

Full members
W. Weiss (Chair), C.-M. Larsson, Chr. McKenney, J.-P. Minon, S. Mobbs, T.
Schneider, H. Umeki

Corresponding members
W. Hilden, C. Pescatore, M. Vesterind

1DRAFT REPORT FOR FOR CONSULTATION

31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74

Radiological protection in geological disposalof long-lived solid radioactive waste
ICRP Publication 1XX

Abstract –This report updates and consolidates previous recommendations of ICRP
related to solid waste disposal (Publications 46, 77, 81). The recommendations givenin this report apply specifically to geological disposal of long-lived solid radioactive
waste. The report explains how the 2007 ICRP System of Radiological Protection
described in ICRP Publication 103 can be applied in the context of the geologicaldisposal of long-lived solid radioactive waste. The report is written as a self standing
document.
The 2007 ICRP System of Radiological Protection maintains the Commission‟s threefundamental principles of radiological protection namely justification, optimisation,and the application of dose limits. The Recommendations evolve from the previous
process-based protection approach using practices and interventions by moving toan approach based on the exposure situation. They maintain the Commission‟scurrent individual dose limits for effective dose and equivalent dose from all regulated
sources in planned exposure situations. They re-enforce the principle of the
optimisation of radiological protection. The Recommendations also include anapproach for developing a framework to demonstrate radiological protection of theenvironment.
This report describes the different stages in the lifetime of a geological disposal
facility and addresses the application of relevant radiological protection principles foreach stage depending on the various exposure situations that can be encountered. In
particular, the crucial factor that influences the application of the protection systemover the different phases in the lifetime of a disposal facility is the level of oversightthat is present. The level of oversight affects the capability to reduce or avoid
exposures. Three main timeframes have to be considered for the purpose ofradiological protection: time of direct oversight when the disposal facility is being
implemented and active oversight is taking place; time of indirect oversight when thedisposal facility is sealed and indirect oversight is being exercised to provide
additional assurance on behalf of the society; time of no oversight when oversight is
no longer exercised because memory is lost.
© 20XX ICRP. Published by Elsevier Ltd. All rights reserved.
Keywords: Geological disposal, Radioactive waste, Protecting future generations

2

DRAFT REPORT FOR FOR CONSULTATION

75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122

Table of Contents

Abstract
Table of Contents
Preface
Executive Summary
1. Introduction
2. Scope of this report
3. Basic values and goals underlying protection for a geological disposal ofradioactive waste
3.1 Values underlying the ICRP principles for protecting future generations
3.1.1 Basic values for the protection of future generations
3.1.2 Basic ICRP principles dealing with future generations
3.2 Geological Disposal: Objective and Implementation steps
3.2.1 Strategies for the management of long-lived solid radioactivewaste
3.2.2 Life phases of a disposal facility and safety analysis process
3.2.3 Relevant timeframes for protection
4. Application of the ICRP system of protection during different timeframes in
the life of a geological disposal facility
4.1 The application of the basic principles “justification”, “limitation” and“optimisation”
4.2 Dose and risk concepts
4.3 Exposure situations associated with geological disposal
4.3.1 Exposure Situations for Waste Emplacement Activities
4.3.2 Exposure Situations for the Emplaced Waste
4.3.3 Natural disrupting events
4.3.4 Inadvertent human intrusion
4.3.5 Summary of relevant exposure situation according oversight
4.4 Optimisation and Best Available Techniques
5. „Endpoint considerations“
5.1 The Representative Person
5.2 Protection of the environment
6. References
Annex 1: The ICRP system of protection, focusing on aspects relevant to thegeological disposal of long-lived solid radioactive waste
Annex 2 ICRP use of „potential exposure“
Annex 3 Technical and management principles and requirements

3

DRAFT REPORT FOR FOR CONSULTATION

123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163

Preface
On February 12, 2010, the Main Commission of the International Commission on
Radiological Protection (ICRP) approved the formation of a new Task Group,
reporting to Committee 4, to develop a report which describes in plain language how
the recommendations given in ICRP Publication 103 can be applied in the context ofthe geological disposal of long-lived solid radioactive waste. The report covers boththe protection of humans (workers and the public) and the environment anddiscusses key issues like the transition from a planned to an existing exposure
situation in case of a loss of control of the waste system as well as the applicability ofdose calculated for the far future for decision aiding. The report updates ICRP
Publication 81.
The report provides guidance on: the basic concepts and terms, eg. the radiation protection principles, thedifferent types of situations (including human actions), dose and risk
constraints;
 the nature and role of optimization (stepwise approach, short term vs. longterm, best available technology);
 the use and application of dosimetric units and concepts (dose and risk
constraints, potential exposures, collective dose, different time frames);
 the role of stakeholder involvement in different stages of planning anddevelopment.
The membership of the Task Group was as follows:
W. Weiss (Chair)
J.-P. Minon
H. Umeki

C.-M. Larsson
S. Mobbs

Chr. McKenney
T. Schneider

The corresponding members were:
W. Hilden

C. Pescatore

M. Vesterind

The Task Group wishes to thank those organizations and staff that made facilities
and support available for its meetings. These include BfS, ARPANSA, NRC, NIRAS,
HPA, CEPN, JAEA, EC, OECD/NEA, IAEA.
The report was approved by the Commission in XX in 2011.

4

DRAFT REPORT FOR FOR CONSULTATION

164
165
166
167
168
169
170
171
172
173

Executive summary(a) This report provides advice on the application of the Commission‟s 2007
Recommendations (ICRP Publication 103) for the protection of humans and theenvironment against any harm that may result from the geological disposal of longlived solid radioactive waste. It illustrates how the key protection concepts andprinciples of ICRP Publication 103 are to be interpreted and how they apply over thedifferent timeframes over which a geological disposal facility for long-lived solidradioactive waste would have to provide radiological protection (see Figure).

Pre-operational phase

Operational phase
Direct Oversight
Waste emplacement

SitingDecision

174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205

Construction
Decision

Decison to
Begin Disposal

Decision on
PartialBackfilling

Post-operational phase
No Oversight

Indirect oversightUndergroundobservation

Decision to End
Emplacing Waste

Repository
closureDecision on
Final Closure

The thickness of the red lines
represents the amount of humanactivity related to the repository

Decision on
follow-up
provisions

Decision on
follow-up
provisions(b) The goal of a geological disposal facility is to isolate and contain the waste inorder to protect humans and the environment for time scales that are comparablewith geological time scales. At great distance from the surface, changes are
particularly slow. With distance from the surface, and having chosen appropriate
sites the potential for human intrusion will be limited. Radioactivity will decrease withtime, and any release would be slowed down and diluted further by a properlychosen geological formation. Geological disposal is recognized by the internationalorganisations as especially intended for high level radioactive waste or spent fuelwhere long term isolation and containment is required. Geological disposal may also
be used for other long-lived wastes since a similar need for long term protection
applies.
(c) The design of a geological disposal facility addresses a series of developmentswith different probabilities that may be defined by regulation. Besides these designbasis developments, the developer / implementer and the regulator may want toassess evolutions in non-design-basis conditions in order to judge the robustness ofthe system.
(d) These ICRP recommendations describe the radiological concepts and criteria that
ought to be used by both the designer and/or operator of the facility and theregulator. For the assessment of the safety and radiological protection of a geologicaldisposal facility for long-lived radioactive waste various dose and risk constraints areused. Optimisation deals with the main aim of a disposal system, i.e., the radiologicalprotection of humans and the environment. Optimisation of protection is the central
element of the step-wise construction and implementation of a geological disposal
facility. It has to cover all elements of the system, including the societal component,in an integrated way. Important aspects of optimisation of protection must occur prior
to waste emplacement, largely during the siting and design phase. The optimisation
efforts can be informed by, and construction supplemented with, consideration ofbest available technique (BAT) as applied to all stages of disposal facility siting and
5

DRAFT REPORT FOR FOR CONSULTATION

206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252

design. During the implementation phase, some further optimisation is possible butvery little can be done to further optimise the performance of the engineered features
after waste emplacement has occurred. In the long term optimisation of protection
can only be achieved if oversight is maintained.
(e) In the distant future the geological disposal facility might give rise to somereleases to the accessible environment and the “safety case” has to demonstrate thatsuch releases, should they occur, are compatible with regulation and radiologicalprotection criteria. In application of the optimisation principle, the reference
radiological impact criterion for the design of a waste disposal facility recommended
by ICRP is an annual dose constraint for the population of 0.3 mSv in a year [ICRP103], without any weighting of doses in the far future. For less likely events resulting
in potential exposures, the Commission continues to recommend a risk 1 constraint forthe population of 1 10-5 per year. However, ICRP Publication 103 also warns that,given the long timeframes considered in waste disposal, the evolution of society,human habits and characteristics is such that effective dose looses its directconnection to health detriment after the time span of a few generations. At the sametime, in the distant future, the geosphere and the engineered system and, even more,
the biosphere will evolve in a less predictable way. The scientific basis for dose andrisk assessments at very long times into the future then becomes questionable andthe strict application of numerical criteria may be inappropriate. Hence, the annual
dose constraint of 0.3 mSv in a year is to be used for the sake of comparison of
options rather than as means of assessing health detriment.
(f) In particular, a crucial factor that influences the application of the protection
system over the different phases during the lifetime of a geological disposal facility, isthe level of oversight that is present. The level of oversight directly affects thecapability to reduce or avoid some exposures. Three main timeframes have to beconsidered: the time of direct oversight when the disposal facility is being
implemented and active oversight is taking place (operational phase); the time ofindirect oversight when the disposal facility is partly (backfilling and sealing of drifts)
or fully sealed (post-closure period) where direct regulatory oversight might be
supplemented or replaced by institutional oversight (e.g. restriction of land use) andthe time of absence of oversight (post-closure period in distant future) in casememory is lost, although the primary objective is to keep memory of the site.
(g) The exposures arising from the design basis evolution of the geological disposal
facility are planned exposure situations as defined in ICRP Publication 103. They
include potential exposures from events with low probability which have to beconsidered as part of the design basis. If severe disturbing events outside the designbasis occur while there is still oversight (direct or indirect) of the disposal facility andwhich result in doses largely exceeding 0.3 mSv in a year, the ensuing situation will
be considered as an emergency exposure situation followed by an existing exposure
situation in case this emergency is resulting in a long lasting contamination of theenvironment. If a severe disturbing event occurs when there is no longer any
oversight of the disposal facility, there is no certainty that a competent authority
would be able to understand what is the source of the exposure and therefore, it is1

Risk is used in this document always to mean radiological risk as defined in ICRP Publication 103.

6

DRAFT REPORT FOR FOR CONSULTATION

253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278

not possible to consider with certainty the implementation of relevant
countermeasures to control the source. However, there is a need to evaluate theconsequences within the scope of an existing exposure situation.
(h) For the “design basis” evolution, the dosimetric criteria relevant to planned
exposure situations will be considered for assessing the safety and robustness of thedisposal facility. For a severe disturbing event, the reference level to be considered
for emergency exposure situation would apply when relevant (i.e. reference level inthe range of 20 to 100 mSv for the first year). It is also necessary to evaluate thepossible consequences of the occurrence of such events on the basis of thedosimetric criteria relevant for existing exposure situation as defined by ICRP (i.e.
reference level of a few mSv per year).
(i) The safety case of a geological disposal facility, by including events that are notexpected to occur with high certainty, includes automatically considerations on how
to deal with potential exposures as defined by ICRP Publication 103 (section 6.1.3).
(j) ICRP recommends that dose or risk estimates derived from these exposure
assessments should not be regarded as direct measures of health effects beyond
timescales of around several hundred years into the future. Rather, they represent
indicators of the protection afforded by the geological disposal system.
(k) The application of the three exposure situations and of dose limits, constraints
and reference levels as defined in ICRP Publication 103 during these timeframes isindicated in Table 1.

7

DRAFT REPORT FOR FOR CONSULTATION

279
RADIOLOGICAL EXPOSURE SITUATIONS AS FUNCTION OF DISPOSAL FACILITY EVOLUTION
AND PRESENCE AND TYPE OF OVERSIGHT

Disposal facility
StatusDirect Oversight

Indirect OversightNo oversightPlanned Exposure2
Situation

Planned Exposure2
Situation

Planned Exposure
2,3
Situation

Non-design basis
evolution involving
significant
exposures topeople and theenvironment

Emergency Exposure
Situation at the time of
exposure, followed by
an Existing
4
Exposure Situation

Emergency Exposure
Situation at the time of
exposure, followed by
an Existing Exposure
4
Situation

Emergency and/or
Existing Exposure
Situation

Inadvertent
Human Intrusion

not relevant

not relevant

Design-basis
evolution

280
281
282
283
284
285
286
287
288
289

Type of Oversight

1

Emergency and/or
Existing Exposure
Situation

1

The design basis is the envelope of both expected and less likely (potential) events that are used in planning thefacility.
2
At design: 20 mSv in a year dose limit to worker and dose constraint to be specified by operators; 1 mSv in ayear dose limit and 0.3 mSv in a year dose constraint for the public, in the case of less likely events within the-5design basis a risk constraint of 1 10 per year for the public is suggested.
3
No worker dose is foreseen during the period of no oversight4
For an emergency exposure situation a reference level between 20 and 100 mSv per year is recommended; foran exisiting exposure situation a reference level should be selected in the lower part of the band between 1
and 20 mSv per year, eg., in the range of a few mSv per year.

8

DRAFT REPORT FOR FOR CONSULTATION

290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338

1. Introduction(1) In the context of the Commission's recommendations, waste is any material forwhich no further use is foreseen. Waste, as generated, includes liquid and gaseous
effluents as well as solid materials. Waste storage is the temporary retention ofwaste. Waste disposal is the permanent isolation and containment of waste in an
appropriate facility. Waste management means the whole sequence of operations
starting with the generation of waste and ending with disposal.
(2) This report deals with geological disposal of long-lived solid radioactive waste
which is intended to isolate and contain especially high level waste, spent fuel andintermediate level wastes containing radionuclides with long half lives. These areconcentrated wastes which contain high specific activities; they need to be handled
remotely, for hundreds or thousands of years. The report does not address nearsurface disposal facilities because they differ from geologic disposal facilities in two
key aspects: the isolation and containment function and the waste for which they areintended.
(3) Technical solutions for the permanent isolation of long-lived, solid radioactive
waste at distances from the surface of hundreds of metres in geological formations
are being developed and pursued in a number of countries. Geological disposal iscurrently recognized by international organisations in charge of radioactive waste
management as especially suited for high level radioactive waste or spent fuel wherelong term containment is required. Geological disposal may also be used for otherwastes containing long lived radionuclides since similar long-term protection
requirements can be formulated. An example of geological disposal is theemplacement of waste in excavated tunnels or shafts, followed by backfilling andsealing of the entire facility.
(4) The goal of a geological disposal facility is to achieve the isolation andcontainment of the waste and to protect humans and the environment for time scales
that are comparable with geological changes. At great distance from the surface,such changes are particularly slow and, at the same time, radioactivity will decrease
with time. Additionally, if a site is chosen in an area with no known natural resources,
the potential for human intrusion will be limited. Finally, a properly chosen geologicalformation would assure stable chemical conditions for the waste. Further, it would
attenuate and slow down any releases of radionuclides. In this context „distance‟ can
imply horizontal or vertical distance as, for example the case of a disposal facility
sited deep within a mountain.
(5) The safety strategy implemented for geological disposal is that to concentrate andretain the waste. No exposure is ever intended, although these may happen. The
disposal facility is thus to be seen as a functional facility whose controls are in-built
and whose safety, after facility closure, does not rely on the presence of man. The
safety function to be fulfilled by a geological disposal facility independent of man is toisolate and contain the waste over as long a period of time as possible. This will allow
radioactive decay to take place and attenuate and delay the eventual release of any
contaminants to the accessible environment. Furthermore, it will reduce the risk of
inadvertent human intrusion. In the situation of a human intrusion the health9DRAFT REPORT FOR FOR CONSULTATION

339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387

consequences for the intruder might be high. But this is an inescapable consequenceof the decision to concentrate waste in a disposal facility.
(6) Geological disposal of long-lived solid radioactive waste poses a number ofchallenges related to radiological protection over extended periods of time, e.g. thenature and role of optimization of protection during the various phases of thedevelopment and implementation of the disposal facility and the applicability of doseand risk calculated for the far future for decision aiding. The report explains how theprotection principles as laid out in ICRP Publication 103 can be applied under thesecircumstances. It also considers elements that can assist in demonstration ofcompliance with the protection principles and how the principles, in broad terms,
relate to other protective goals that would be considered in an environmental impact
assessment/statement.
(7) Radiological protection is only one set of the protection concepts that will be usedby safety analysts in documenting the protection capability of the disposal facility.
Other concepts may relate to the protection of resources in a sustainable way suchas for example groundwater as a drinking water resource. The chemical toxicity of
the waste or the waste containment system in a disposal facility for radioactive waste
may be a further issue of concern. Optimal protection would be achieved by theapplication of an integrated framework of protection concepts in which the level ofprotection of humans, the environment and the resources are comparable forradiotoxic and chemotoxic substances.
(8) The Commission has previously published protection recommendations for the
disposal of long-lived radioactive waste (ICRP Publications 46, 77, 81) consistent
with its general recommendations for the application of its overall System ofRadiological Protection (ICRP Publication 60). More recently, the Commission has
published new general recommendations (ICRP Publication 103). This reportsummarizes and explains how these recommendations specifically apply to ageological disposal facility for long-lived solid radioactive waste.
(9) This report is written as a stand-alone presentation of the Commission's
Publication 103 system of radiological protection as it should be applied in thecontext of geological disposal of long-lived radioactive waste. It covers all issues
related to radiological protection of humans and the environment against harm that
may result from the geological disposal of long-lived solid radioactive waste. Where
the Commission‟s recommendations are unchanged, or issues are addressedsufficiently in publications by other international organisations, references are given
and no detailed discussion is provided.
(10) In the case of geological disposal, the occupational exposure of workers and theexposure of the public are managed in accordance with the ICRP system ofprotection. The main protection issue dealt with in this report concerns exposuresthat may or may not occur in the far future. Any corresponding estimates of doses toindividuals and populations will have growing associated uncertainties as a functionof time due to incomplete knowledge of the future disposal system behaviour, ofgeological and biospheric conditions, and of human habits and characteristics.
Furthermore, due to the long timescales, verification that protection is being achieved
10

DRAFT REPORT FOR FOR CONSULTATION

388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436

cannot be expected in the same manner as for current discharges since knowledgeof the disposal facility may eventually be lost and oversight may be absent. Neither
can it be assumed that effective mitigation measures will necessarily be carried out,
should they be required in the far future. Nevertheless, the Commission's system ofprotection can be applied to the disposal of long lived solid radioactive waste, with
due interpretation.
1.1 References
ICRP (1985) Protection Principles for the Disposal of Solid Radioactive Waste. ICRP
Publication 46, Annals of the ICRP 15 (4).
ICRP (1991) 1990 Recommendations of the International Commission on
Radiological Protection. ICRP Publication 60, Annals of the ICRP 21 (1–3).
ICRP (1997) Radiological Protection Policy for the Disposal of Radioactive Waste.
ICRP Publication 77, Annals of the ICRP 27 Supplement 1997.
ICRP (1998) protection recommendations as applied to the disposal of long-lived
solid radioactive waste. ICRP Publication 81, Annals of the ICRP 28 (4).
ICRP (2007). The 2007 Recommendations of the International Commission on
Radiological Protection. ICRP Publication 103, Annals of the ICRP 37 (2–4).
2. Scope of this report(11) This report deals with the radiological protection of workers, members of the
public and the environment, following the disposal of long-lived solid radioactive
waste in geological disposal facilities. The recommendations given in this report
apply to disposal facilities where there is still an opportunity for their implementation
during the site selection, design, construction, and operational phases. They should
also be taken into account in the justification of decisions involving practices
generating waste.
(12) The report does not describe the disposal safety assessment in detail. It rather
provides a description of how protection criteria can be used in the safety analysis,
and establishes recommendations on protection issues related to the disposal of
long-lived solid radioactive waste. Exposures are estimated in order to place
adequate control on the source of exposure. The characteristics and habits of
exposed individuals and populations are taken into account.
(13) The report does not address near surface facilities because they differ fromgeological facilities with respect to the isolation function and the waste for which they
are intended. Near surface facilities principally rely on the engineering containment
provided by the facility and on the presence of man. The long term stability of thesurrounding soil or rock and its attenuation properties are of secondary importance.
Also, they are by definition more easily accessible and hence a near surface facility
can only provide short term isolation of the waste. Near surface facilities are suitable
for low and intermediate level wastes containing predominantly shorter lived and lessconcentrated levels of radionuclides. The differences in the functions of near surface
facilities and geological facilities, together with the different wastes they receive,
result in the application of specific regulatory regimes: one for near surface disposal
and one for geological disposal. Previous ICRP recommendations for the radiological
11

DRAFT REPORT FOR FOR CONSULTATION

437
438
439
440

protection of workers, members of the public and the environment in the case of nearsurface disposal facilities or other disposal options are still valid.

12

DRAFT REPORT FOR FOR CONSULTATION

441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489

3. Basic values and goals underlying protection for a geological disposal ofradioactive waste
3.1 Values underlying the ICRP principles for protecting future generations
3.1.1 Basic values for the protection of future generations(14) The initial composition of radionuclides contained into long lived radioactive
waste evolves over time, changing the nature of the hazard. At the same time, eventhough the activity decreases with time, the halflife of some radionuclides, and therate of ingrowth of others, are such that some of these wastes may never beconsidered as not being a hazard.
(15) Over the last decade, reflections on safety and societal issues associated withthis long-term dimension clearly point out the complexity of the situation: on one hand
it is not possible to envisage how the society will be organized in the far future whileon the other hand the current generation has to take care of the possible future inorder to design the waste management strategy. This is notably the core of the
ethical reflections regarding the precautionary principle and sustainable
development, in order to preserve the resources and the environment for the future
generations.
(16) The 1997 Joint Convention on the Safety of Spent Fuel Management and on the
Safety of Radioactive Waste Management details the long-term aspects of the safety
objectives for disposal by requiring to meet the principle that “…individuals, society
and the environment are protected from harmful effects of ionising, now and in the
future, in such a way that the needs and aspirations of the present generation are
met without compromising the ability of future generations to meet their needs andaspirations” (IAEA 1997). In a broad sense this principle is consistent with one of therecommendations of ICRP Publication 77: “the Commission recommendations relyon the basic principle that individuals and populations in the future should be afforded
at least the same level of protection as the current generation.” These
recommendations were further expanded and clarified in ICRP Publication 81(paragraphs 41 and 42).
(17) In the same vein, the obligations of the present generation toward the future arecomplex, involving, for instance, not only issues of safety and protection but also oftransfer of knowledge and resources. Due to the technical and scientific uncertainties
and to the evolution of society in the long-term, it is generally acknowledged that thecapacity of the present generation to guarantee delivery of its obligations diminisheswith distance in time.
3.1.2 Basic ICRP principles dealing with future generations(18) The main strength of ICRP consists in its unified protection system applicable toall types of exposure situations. In its 2007 Recommendations (ICRP Publication
103), the ICRP protection system continues to rely on its three fundamental
principles: justification, optimisation of protection and application of dose limits,
applied according to the exposure situation considered.
13

DRAFT REPORT FOR FOR CONSULTATION

490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538

(19) The optimisation principle is of primary importance and its role has been
reinforced in the new ICRP Recommendations. For this purpose, ICRP recommends
that, in assessing the level of protection for humans, “the likelihood of incurringexposures, the number of people exposed, and the magnitude of their individual
doses should all be kept as low as reasonably achievable, taking into accounteconomic and societal factors” (ICRP Publication 103, paragraph 203).
(20) For this assessment, two concepts are considered by ICRP: dose and risk.
Associated with dose and risk, the concept of health detriment, as introduced by
ICRP in its Publication 26, is also a key concept to consider for assessing the level ofprotection. The application of this concept aims at providing an estimate of the total
harm to health to individuals and their descendants as a result of an exposure,assuming a linear-non-threshold dose-effect relationship. For exposures that may
occur in the long-term, the relevance and meaning of dose and risk is of interest andtheir interpretation over the different time periods has to be clarified. It should be
noted that the knowledge of the relationship between dose and effect may very wellchange in the future, as has already been demonstrated by past reassessments ofnominal probability coefficients. Likewise, the ability to cure or mitigate induced
health effects may change in the future. It is not possible to make any prediction of
the direction of these changes. Thus, the efforts to avoid and/or reduce any effect onhuman health and on the environment in the far future have to be entirely guided by
the current understanding of health and environmental effects.
(21) Notwithstanding the uncertainty described above, the ICRP dosimetric quantities
and the health detriment can be used for long-term assessment. In fact, theassessment of the robustness of the protection system provided by solid waste
disposal in the long-term does not need a precise knowledge of the evolution of thegeneral health of the population in the far future. At the design stage, what is at stakeis not to evaluate what would be the level of health effects in a group of population in
the far future. The challenge is rather to estimate, in an optimisation process througha comparison (using dose and risk indicators) of alternative options, the levels ofprotection achieved by a given disposal facility system and to judge if the estimatedprotection level of the chosen strategy is acceptable in the light of the level ofprotection accepted today.
3.2 Geological disposal: Objective and Implementation steps
3.2.1 Strategies for the management of long-lived solid radioactive waste(22) Because of the nature and longevity of hazards, the fundamental strategy
adopted for the management of long-lived radioactive waste in order to achieve thesafety objective is to concentrate and contain the wastes and to isolate them from theenvironment as long as possible. The goal of a geological disposal facility is toprovide protection of humans and the environment from the hazards that theradioactive waste and the waste containment system would pose over time. The
current generation has to take care of the possible future developments when
designing the waste management strategy. These possible developments imply
different timescales with different levels of presence of human institutions but also
14

DRAFT REPORT FOR FOR CONSULTATION

539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579

uncertainty concerning the level of presence of humans themselves.
(23) It is internationally recognized that only materials that have been declared ashaving no further use for society (waste) are disposed of, so that there is no intention
by the current generation to retrieve it, even if technical options to do that wereavailable. Disposal is not to be confused with a storage situation. Currently, thereference option is to dispose of these wastes in engineered deposition facilities
located in suitable geological formations [IAEA 1997, OECD-NEA 2008].
(24) A step-wise process, involving various stakeholders, is considered as a
responsible approach to planning for the disposal development and implementation,
including final closure. In that context the concepts of reversibility and retrievability
into the disposal facility programmes are also considered. Reversibility implies a
disposal programme that is implemented in stages, keeps options open at eachstage, and provides the capacity to manage the disposal facility with flexibility overtime. Retrievability is the possibility to reverse the step of waste emplacement during
the entire operational phase, e.g. before final closure of the disposal facility.
Retrievability does not imply the intention to retrieve nor is retrieval a contingency
plan for the disposal facility. The key is to consider any choices that could facilitate
retrieval if this was ever required but to continue to ensure that the integrity of the
facility is not jeopardised by these choices. The decision to actually carry out any
retrieval would be a separate decision taken in the future, according to theradiological principles that apply to a new planned activity.
(25) The “concentrate and contain” strategy makes it possible, in principle, for thewaste to be re-accessed either voluntarily or involuntarily at some time in the future.
Therefore, disposal systems ought to be designed to reduce the possibility of
inadvertent or malevolent events. There are to some extent conflicting requirements
involved and a balance has to be found in each case, taking into consideration thetimescales, the nature of the waste, the nature of the host geological formation, andthe evolving desires of society.
3.2.2 Life phases of a disposal facility and the safety analysis process(26) With respect to the presence of man for managing the facility, the developmentof a geological disposal facility involves three main phases (Fig. 1) whose durations
vary amongst national programmes depending on the design and on each country‟s
approach to decision making.
Fig. 1 Disposal facility life phases and relevant oversight periods

Pre-operational phase

Operational phase
Direct Oversight
Waste emplacement

SitingDecision

580

Construction
Decision

Decison to
Begin Disposal

Decision on
PartialBackfilling

Post-operational phase
No Oversight

Indirect oversightUndergroundobservation

Decision to End
Emplacing Waste

Repository
closureDecision on
Final Closure

The thickness of the red lines
represents the amount of humanactivity related to the repository

Decision on
follow-up
provisions

Decision on
follow-up
provisions

15

DRAFT REPORT FOR FOR CONSULTATION

581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629

(27) The pre-operational phase: During this phase, the disposal facility is designed,
the site is selected and characterized, the man-made materials are tested and theengineering demonstrated, safety cases for operational and post-operational phases
are developed, the licenses for building and operation are applied for and received,and construction begins. A baseline of environmental conditions is also performed.
(28) The operational phase: During this phase, the emplacement of waste is
performed, followed by a period of observation prior to the closure. At one time
during this phase, some galleries will be filled and sealed and will have thus reachedtheir final configuration, while others will still be excavated.
This phase will be under direct oversight of the safety authorities in cooperation
with other relevant stakeholders and it may be divided into three relevant time
periods:- The emplacement period: A licence is granted that authorizes the transfer
and emplacement of waste packages to underground in pre-excavatedgalleries, rooms, and/or boreholes. The environmental conditions arecontinuously monitored and compared to the baseline data. Research anddevelopment continues. The regulator performs regular inspections of theunderground operations. The long-term safety case is regularly updated andreviewed by the regulator. In this phase, new underground galleries may bebuilt and partial backfilling and/or sealing of galleries and disposal facility
areas may also take place.
- The observation period: After all waste packages are emplaced it might bedecided to monitor (parts of) the disposal facility and to keep someaccessibility to at least part of the waste while additional performance
confirmation takes place.
- The closure period: A license to close is granted and access from thesurface to the underground facility is terminated. Backfilling and sealing are
performed according to design. Surface facilities may be dismantled. The
archives of all relevant information are to be provided for long-termpreservation.
(29) The post-operational phase: during this phase the presence of man is nolonger required to directly manage the facility. This phase is the longest one,and is divided into two relevant time periods:- The period of indirect oversight: After closure, safety is assured totally
through the intrinsic, built-in provisions of the design of the disposal facility.
Nevertheless, it is expected to continue monitoring of the baseline
environmental conditions including some remote monitoring. Archives ontechnical data and configuration of waste packages and the disposal facility
will be kept, as well as markers to remind coming generations of its existence.
The relevant international safeguards controls continue to apply. Inadvertent
human intrusion in the disposal facility can be ruled out.
- The period of no oversight: Although termination of indirect oversight is notforeseen, it will still have to be considered in the design and planning stage as
there is no guarantee that it will be maintained as well as the memory of the
16

DRAFT REPORT FOR FOR CONSULTATION

630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653

(30) As long as oversight is effective, it will be possible to evaluate the protection
capability of the disposal facility based on regular updates of the safety case. The
safety case provided by the developer of a disposal facility must address theoperational and the post-operational phase and, specifically the distant future, whencontrols and interventions cannot be relied upon. The aim of the developed safetycase is to provide convincing evidence of the intrinsic protective capability of thesystem. The safety case shows how the barriers in the disposal facility system work
together and how they fulfil their desired functions over time. It documents theprinciples and strategies that were followed for developing the knowledge base. It
recognises the residual uncertainties in both the long-term processes and potential
future events that may affect the performance of the disposal facility and why thesehave been considered as not to reduce protection unduly. Interactions with thevarious stakeholders - e.g., the local public, outside experts brought in to conduct
independent reviews - are acknowledged elements to enhance the quality of thedecision-making process at the different phases of the disposal facility development
and implementation.

654

3.2.3 Relevant timeframes for radiological protection

655
656
657
658
659
660
661
662

(31) As stated before, the scope of this ICRP report is the description of how
protection criteria can be used in the safety assessment, and to establish
recommendations on protection issues related to the disposal of long-lived solidradioactive waste. One of the crucial factors that influences the application of theprotection system over the different phases in the lifetime of a disposal facility is thelevel of oversight that is present. The level of oversight will directly affect thecapability to reduce or avoid some exposures. Three main timeframes have to beconsidered:

663
664
665
666
667
668
669
670
671
672
673
674

site in the distant future. Eventually, loss of oversight and memory may takeplace, either progressively or following major unpredictable events such as
war or loss of records. Therefore, inadvertent human intrusion in the disposal
facility cannot be ruled out during this time period. The intrinsic hazard of thewaste will decrease with time but it may continue to pose a significant hazard
for a considerable time. The loss of oversight does not result in a change ofthe protection capability of the disposal facility.

Time of direct oversight: when the disposal facility is being implemented
and active oversight is taking place. This timeframe coincides with the preoperational and operational phases of the disposal facility;
Time of indirect oversight: when the disposal facility is sealed and indirectoversight is being exercised to provide additional assurance on behalf of thesociety. This timeframe coincide with the post-operational phase of thedisposal facility.
Time of no oversight: when oversight is no longer exercised because
memory is lost. This timeframe coincides with the post-closure period in the
distant future.

The transition between the different timeframes has also to be considered

17

DRAFT REPORT FOR FOR CONSULTATION

675
676
677
678
679
680

(32). During the time of direct oversight both the operator and the regulator ininteraction with the concerned stakeholders will be able to actively manage theprotection of workers, the public and the environment through direct and indirect
actions. The transition from this timeframe into the timeframe of indirect oversight is
not abrupt. Thus parts of the disposal facility will be under direct oversight, and at thesame time others will be under indirect oversight.

681
682
683
684
685
686
687
688
689

(33) During the time of indirect oversight, there might be some presence ofpeople/staff/operator at the site. Knowledge is maintained, monitoring may continue
to occur and some corrective actions could be made if needed. However, in mostcases, options to address radiological protection will be indirect. As time progresses
the degree of oversight may change, corresponding, for example, to less frequent
inspections. The decisions to reduce the level of oversight would be based to someextent on the degree of confidence in the behavior of the facility, and other societal
and economic factors. Decisions related to the organization and evolution of theoversight should be discussed with the stakeholders concerned.

690
691
692

(34) It is to be expected that regulators and society will maintain forms of oversightand memory as long as possible. However, there is no guarantee on there existencein the distant future. At this point the facility implicitly leaves the regulatory regime.

693
694
695
696
697
698
699

(35) No matter in which way oversight ceases to exist, the disposal facility is still afunctioning facility and continues to be so. The potential to isolate and contain theradioactive waste is an inherent feature of the radioactive waste disposal facility that
continues into the far future and responds to the considered evolution of the disposal
facility under natural processes and events. The multi-barrier, multi-function systemthat is at the basis of the disposal facility design must have the potential to constrain
releases of radionuclides from the radioactive waste disposal facility.

700
701
702
703
704
705
706
707
708
709
710
711

(36) Another type of passive control that may continue after the direct oversightceases is provided by memory or records of the presence of a geological disposal
facility or other measures decided by the authorities in interaction with the different
stakeholders, however for a much shorter timescale. This reduces the probability of
direct inadvertent intrusion by people into the facility and it may assist in thejustification and planning for any advertent intrusion, if desired. At some point in the
distant future, the memory of the presence of the disposal facility may be lost andthere is no defense mechanism against direct inadvertent intrusion, apart from thefact that the waste is out of sight and stored at great distance from the part of thebiosphere that people normally inhabit. The location of the geological disposal facility
and its technical design will constitute the remaining built-in “control” against
inadvertent intrusion.

712
713
714
715
716

(37) The cessation of direct oversight of the site will not occur before tens tohundreds of years after the start of operations. It is not possible to specify the criteriathat will be used by the people making decisions at that time. The different decisions
to be made related to the evolution of the oversight should be discussed with thestakeholders.

18

DRAFT REPORT FOR FOR CONSULTATION

717
718
719
720
721

(38) As such, the assumption that cessation of indirect oversight will occur does notcorrespond to a regulatory decision to release radioactive materials from regulatory
control.

19

DRAFT REPORT FOR FOR CONSULTATION

722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770

4. Application of the ICRP system of protection during different timeframes in
the life of a geological disposal facility(39) The major features of the 2007 ICRP Recommendations (ICRP Publication 103)
relevant to this report are:
 Maintaining the Commission‟s three fundamental principles of radiologicalprotection, namely justiﬁcation, optimisation, and the application of dose limits,and clarifying how they apply to sources delivering exposure and to individuals
receiving exposure.
 Evolving from the previous process-based protection approach using practices
and interventions, by moving to a situation-based approach applying thefundamental principles of justiﬁcation and optimisation of protection to allcontrollable exposure situations, which the 2007 ICRP Recommendations
characterise as planned, emergency, and existing exposure situations.
 Re-enforcing the principle of optimisation of protection, which should beapplied in a similar way to all exposure situations, with restrictions on
individual doses and risks, namely dose and risk constraints for planned
exposure situations and reference levels for emergency and existing exposure
situations.
4.1 The application“optimisation”

of

the

principles“justification”,“limitation”and(40) The deﬁnitions of the three basic principles and basic considerations for theirapplication to waste disposal are described as follows.


The Principle of Justiﬁcation: “Any decision that alters the exposure situation
should do more good than harm.”
Waste management and disposal operations are an integral part of thepractice generating the waste. It is wrong to regard them as a free standing
practice that needs its own justification. The waste management and disposal
operations should therefore be included in the assessment of the justificationof the practice generating the waste (ICRP 77 §34). This assessment should
include considerations of different options for waste management and disposal
including the justification of these options. If the national waste disposal policy
has changed and the practice is continuing, it may be necessary to reassess
the justification of the practice. If the practice has ceased, the protection
strategy, rather than the practice, has to be considered for justification.



The Principle of Optimisation of Protection: “The likelihood of incurringexposure, the number of people exposed, and the magnitude of theirindividual doses should all be kept as low as reasonably achievable, taking
into account economic and societal factors.”
As clearly stated in ICRP Publication 103, optimisation is of primary
importance and its role has been reinforced. This is also the key principle
guiding the application of the ICRP system of protection in the disposal of
long-lived solid radioactive waste, as discussed in this report (for details see
section 4.4).

20

DRAFT REPORT FOR FOR CONSULTATION

771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817



The Principle of Application of Dose Limits: “The total dose to any individualfrom regulated sources in planned exposure situations other than medical
exposure of patients should not exceed the appropriate limits speciﬁed by theCommission.”
The general statement of ICRP Publication 81 (paragraph 36) still applies:“Although the Commission continues to recommend dose limits, it recognisesthat `dose limits for public exposure are rarely limiting in practice' (ICRP,
Publication 77, 1997b, paragraph 36). Furthermore, it considers that `...theapplication of dose limits to waste disposal has intrinsic difficulties' (ICRP,
Publication 77, 1997b, paragraph 19) and that control of public exposure
through a process of constrained optimisation will `obviate the direct use of the
public exposure dose limits in the control of radioactive waste disposal' (ICRP,
Publication 77, 1997b, paragraph 48).”

4.2 Dose and risk concepts(41) The main and primary use of the effective dose in radiological protection for both
workers and the general public is (ICRP Publication 103, paragraph 153):
 The prospective dose assessment for planning and optimisation of protection.
 The retrospective dose assessment for demonstrating compliance with dose
limits, or for comparing with dose constraints or reference levels.
In practical radiological protection applications, effective dose is used for thedemonstration of compliance with protection standards.
(42) A potential exposure is an exposure that is not expected to be delivered withcertainty but that may result from an accident at a source or an event or sequence of
events of a probabilistic nature, including equipment failures and operating errors.
The risk associated with such an event is a function of the probability of anunintended event causing a dose, and the probability of detriment due to that dose.
Risk constraints correspond to dose constraints but refer to potential exposures. For
potential exposures of workers, the Commission continues to recommend a genericrisk constraint of 2 10-4 per year which is similar to the probability of fatal cancer
associated with an average occupational annual dose of 5 mSv (ICRP Publication
76). For potential exposures of the public, the Commission continues to recommend
a risk constraint of 1 10-5 per year.
4.3 Exposure situations associated with geological disposal(43) The ICRP system of protection described in its Publication 103 distinguishes
three types of radiological situations: planned, existing and emergency situations(ICRP Publication 103, paragraph176).
“Planned exposure situations are everyday situations involving theoperation of deliberately introduced sources including decommissioning,
disposal of radioactive waste including the post-closure phase andrehabilitation of the previously occupied land. Planned exposure situations
may give rise both to exposures that are reasonably anticipated to occur(normal exposures) and to higher exposures that are anticipated to occur with21

DRAFT REPORT FOR FOR CONSULTATION

818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866





a lower likelihood (potential exposures). These may arise following deviations
from normal operating procedures, but are considered at the planning stage.”“Emergency exposure situations are situations that may occur during theoperation of a planned situation, or from a malicious act, or from any otherunexpected situation, and require urgent action in order to avoid or reduce
undesirable consequences.”“Existing exposure situations are exposure situations that already exist
when a decision on control has to be taken, including prolonged exposure
situations after emergencies.”

4.3.1 Exposure situations for waste emplacement activities(44) In terms of the basic types of exposure situations, waste emplacement activities
are subject to the same principles of dose limitations and the requirement to optimise
below constraints as those in any nuclear facility. Both worker and public exposuresare expected from the transportation, handling and disposal activities and thus, areplanned exposures including potential exposures from deviations from the normal
operations. The possibility also exists for incidents due to low probability/highconsequence initiating events, which could lead to an emergency situation.
Operations would be expected to be optimized consistent with the Commission‟s
Recommendations in ICRP Publication 103. The annual dose limits for worker of e.g.
20 mSv in a year is applied with the obligation of optimising protection below dose
constraints to be specified by operators. The recommended dose constraint for the
public is 0.3 mSv in a year. At the end of the period of direct oversight worker
exposures are to be considered in two limited areas of exposure: (1) worker
exposure for any indirect monitoring of the facility and its surroundings during theperiod of indirect oversight, and (2) exposure due to residual radioactivity after
decommissioning of the surface facilities.
4.3.2 Exposure situations for the emplaced waste(45) For the emplaced waste, a typical disposal facility safety assessment would
suggest that significant releases are unlikely during the emplacement period and theperiod of time during which a competently sited, operated and sealed disposal facility
is being actively observed and monitored. Therefore, any exposures would be
categorised as part of the potential exposure subset of planned exposure. Given thepotentially vast time periods involved in the period of no oversight, the possibility ofan eventual release of some radioactive substances is inherent in the concept ofgeological disposal even if the system operates as intended (i.e., without deviations
from procedures in operations, construction or accidents). These very long term
potential releases of radioactive substances and subsequent exposures are assumed
to result from a variety of scenarios. While they may be foreseen and perhaps
assigned a probability they are still intrinsically uncertain. Evaluations of these
exposures serve the purpose of comparing alternative facility design options andreaching a regulatory judgment regarding the capability of the system to isolate andcontain the waste. Such evaluations are not considered to be predictions, nor are
they intended to be used for the protection of specific individuals or populations.
Such exposures may in fact be projected to occur at such distant times thattraditional concepts such as dose and risk have to be used with caution.
22

DRAFT REPORT FOR FOR CONSULTATION

867
868
869
870
871
872
873
874

(46) Any such releases would be expected to take place well beyond the operational
period of the facility so that the immediate causes of any release would be beyond
the control of the operator; this suggests that these are uncertain and hence treatedas potential exposures. The timing and magnitude of such releases is not predictable
except in the broadest sense. Even more, the presence of exposed populations at
the point of release as well as their capability to implement protective and/or
corrective actions in the far future cannot be assumed certain, should such releases
occur.

875
876
877
878
879
880
881
882
883
884
885

(47) The process of evaluating the potential exposure from emplaced waste includes
the understanding of the potential ways by which the radionuclides could be released
from the engineered facility, including the transport through the geosphere to thebiosphere and the resultant release into an appropriate environmental compartmentthat could give rise to exposures to humans, flora or fauna. Depending on the level ofknowledge, probabilities may be estimated for these release scenarios. However, atthe long timescales considered in geological disposal, evolution of the biosphere and,possibly, the geosphere and the engineered system will increase the uncertainty ofthese probabilities. Hence the scientific basis for dose and risk assessments at very
long times into the future may become questionable and the results of suchassessments would then need to be interpreted in a qualitative way.

886
887
888
889
890
891
892
893

(48) The expected evolution of a geological disposal facility in the distant future
should not require active involvement to mitigate the consequences as this is counterto the principle of avoiding placing an undue burden on future generations.
Therefore, the Commission continues to support its recommendations in ICRP
Publication 103 that either a dose constraint of 0.3 mSv in a year or an annual risk
constraint of 1x10-5 be used for potential exposures from the emplaced waste. As
noted in ICRP Publication 103, it may be useful to disaggregate the probability andpotential consequence to reach risk-informed decisions.

894
895
896
897
898
899
900
901
902

(49) In the distant future, in case oversight provisions are no longer operational andthe memory of the presence of the disposal facility is lost, it is possible that people
will „rediscover‟ the disposal facility. This may be without compromising its integrity(eg. remote sensing), by observing very small discharges into the biosphere, or it
may be by directly breaching the containment, albeit inadvertently, and causing
contamination of the environment. Situations of this kind would be treated as anexisting exposure situation and be handled as appropriate to the protection
guidelines at the time. However, these guidelines are inherently unknowable andthus, while noted, are not relied on for protection decisions today.

903

4.3.3 Natural disruptive events

904
905
906
907
908
909

(50) The disposal facility and its surrounding environment could be impacted oraltered by natural disruptive events, e.g., earthquakes, during the periods of indirectoversight or no oversight. Different scenarios can be envisaged in the futureaccording to the current knowledge. For these events, it may be possible to estimate
or bound the probability of occurrence, and the risk of potential consequences should
be taken into account in reaching risk-informed waste management decisions.

23

DRAFT REPORT FOR FOR CONSULTATION

910
911
912
913
914
915
916
917
918
919
920

(51) Natural disruptive events with very low probability compared to the design-basis
may occur and may induce significant disturbances on the disposal system or the
migration of the radioactive substances. Examples of these types of events include
major landform change due to tectonic events, etc. Assessing their probabilities ofoccurrence may neither be relevant nor feasible. The Commission recommends thatthe regulatory authority develop a strategy for addressing such events with the
involvement of relevant stakeholders. Possible approaches include establishing aprobability value for which events with lesser probabilities are excluded fromconsideration in the risk-assessment process, optimizing site selection to minimize
the probability of such events, or assessing specific events through stylized
assessments.

921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938

(52) Previously the Commission considered all natural events, disruptive or not,within the same framework (Publication 81). Now, the Commission recommends
separate consideration of natural disruptive events which are included in the designbasis evolution from those which are not. For the first ones, the Commission
recommends application of the dose or risk constraints for planned exposure
situation. For the severe natural disruptive events not taken into account in thedesign-basis evolution, the Commission now recommends application of thereference levels for emergency or existing exposure situations, depending on theseverity of the consequences. If the events were to occur, while there is still (direct orindirect) oversight of the disposal facility, the authorities should be in a position to
implement adequate protection measures to deal with this situation as emergency or
existing exposure situation. If such a disruptive event occurs when oversight of thedisposal system has disappeared, there is no certainty about the possibility that anorganisation could be aware of the disturbance and therefore, it is not possible toconsider with certainty the implementation of protective measures. If the authorities
eventually became aware of the disturbance they would treat the situation as an
emergency exposure situation or an existing exposure situation depending on theseverity of the disturbance.

939
940
941
942
943

(53) For emergency exposure situations, the Commission recommends selection of areference level in the range of 20 mSv to 100 mSv for the first year and developmentof protection strategies to reduce exposures to as low as reasonably achievablebelow the reference level taking into account economic and societal factors(Publication 109).

944
945
946
947
948
949

(54) According to Publication 103, long-lasting exposures resulting from natural
disruptive events (with or without an emergency phase) should be referred to as anexisting exposure situation and the recommended reference levels to be selected for
optimizing protection strategies ranges between 1 to 20 mSv per year. In agreementwith the Commission's recommendations in Publication 111, a reference level should
be selected in the lower part of the band, e.g., in the range of a few mSv per year.

950

4.3.4 Inadvertent human intrusion

951
952
953
954

(55) In general, waste is disposed in a geological disposal facility if it needs to beisolated from possible human intrusion (IAEA, 2009). It is necessary to distinguishbetween deliberate and inadvertent human intrusion into the facility. The first one is
not discussed further in this report as it is considered out of the scope of24

DRAFT REPORT FOR FOR CONSULTATION

955
956
957

responsibility of the current generation to protect a deliberate intruder, i.e. a person
who is aware of the nature of the facility. The design and siting of the facility will haveto include features to reduce the possibility of inadvertent human intrusion.

958
959
960
961
962
963
964
965

(56) A release resulting from inadvertent human intrusion, such as drilling into thefacility, could migrate through the geosphere and biosphere resulting in exposuresthat are indirectly related or incidental to the intrusion event. It is also possible that
inadvertent human intrusion could bring waste material to the surface and hence leadto direct exposure of the intruder and nearby populations. This introduces thepossibility of elevated exposures and significant doses which is an inescapableconsequence of the decision to isolate and contain waste rather than diluting or
dispersing it.

966
967
968
969
970
971
972
973
974
975

(57) Protection from exposures associated with human intrusion is best
accomplished by efforts to reduce the assumed possibility of such events. Thesemay include siting a disposal facility at great distance from the surface, avoiding
assumed valuable resources, incorporating robust design features which makeintrusion more difficult, or employing direct oversight (such as restricting access ormonitoring for releases) and indirect passive oversight (such as archived record andsite markers). While the actual probability of human intrusion at a specific site islargely unknowable as it is based on future human actions, it is assumed that theprobability of intrusion during the direct and indirect oversight periods is effectively
zero.

976
977
978
979
980
981
982
983
984
985
986
987

(58) For longer time periods, in case oversight has disappeared, the occurrence ofhuman intrusion cannot be totally ruled out. Therefore, the consequences of one ormore plausible stylised intrusion scenarios should be considered by the decisionmaker to evaluate the resilience of the disposal facility to potential inadvertent
intrusion. Any estimates of the magnitude of intrusion risks are by necessity
dependent on assumptions that are made about future human behavior. Since noscientific basis exists for predicting the nature or probability of future human actions,the Commission continues to consider not appropriate to include the probabilities ofsuch events in a quantitative performance assessment that is to be compared withdose or risk constraints (Publication 81). If recognized at the time an intrusion occurs,
it would be treated as an emergency exposure situation or an existing exposure
situation depending on the severity of the related disturbance.

988
989
990
991
992
993
994
995
996

(59) The Commission wishes to emphasise that the dose criteria specified in
Publication 81 for human intrusion only apply to near surface disposal. In case ofgeological disposal, intrusion means that many of the barriers which were consideredin the optimization of protection for the disposal facility have been by-passed. Since afuture society may be unaware of the radiation risk associated with such events, any
protective actions required should be considered during the development of thedisposal system. Therefore the dose or risk constraints recommended by theCommission for the application of the optimization of protection in geological disposal
do not apply to inadvertent human intrusion.

997
998
999

4.3.5 Summary of relevant exposure situation according oversight(60) The application of the three exposure situations and of dose limits, dose25

DRAFT REPORT FOR FOR CONSULTATION

1000
1001
1002
1003

constraints and reference levels as defined in ICRP Publication 103 during thesetimeframes is indicated in Table 1.

26

DRAFT REPORT FOR FOR CONSULTATION

1004
RADIOLOGICAL EXPOSURE SITUATIONS AS FUNCTION OF DISPOSAL FACILITY EVOLUTION
AND PRESENCE AND TYPE OF OVERSIGHT
Disposal facility
StatusDirect Oversight

Indirect OversightNo oversightPlanned Exposure2
Situation

Planned Exposure2
Situation

Planned Exposure
2,3
Situation

Non-design basis
evolution involving
significant
exposures topeople and theenvironment

Emergency Exposure
Situation at the time of
exposure, followed by
an Existing
4
Exposure Situation

Emergency Exposure
Situation at the time of
exposure, followed by
an Existing Exposure
4
Situation

Emergency and/or
Existing Exposure
Situation

Inadvertent
Human Intrusion

not relevant

not relevant

Emergency and/or
Existing Exposure
Situation

Design-basis
evolution

1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032

Type of Oversight1

1

The design basis is the envelope of both expected and less likely (potential) events that are used in planning thefacility.
2
At design: 20 mSv/a dose limit to worker and dose constraint to be specified by operators; 1 mSv/a dose limit
and 0.3 mSv/a dose constraint for the public; in the case of less likely events within the design basis a risk
-5constraint of 1 10 per year for the public is suggested.
3
No worker dose is foreseen during the period of no oversight4
For an emergency exposure situation a reference level between 20 and 100 mSv per year is recommended; foran exisiting exposure situation a reference level should be selected in the lower part of the band between 1 and
20 mSv per year, eg., in the range of a few mSv per year.

4.4 Optimisation and Best Available Techniques(61) The principle of optimisation is defined by the Commission (ICRP Publications
101 and 103) as the source-related process to keep the likelihood of incurringexposures (where these are not certain to be received), the number of people
exposed, and the magnitude of individual doses as low as reasonably achievable,
taking economic and societal factors into account. The general recommendations forthe optimisation process are described in ICRP Publication 101, part 2.
(62) The ICRP principle of optimisation of radiological protection when applied to thedevelopment and implementation of a geological disposal facility has to beunderstood in the broadest sense of an iterative, systematic and transparent
evaluation of options for enhancing the protective capabilities of the system and for
reducing impacts (radiological and others).
(63) Optimisation of protection has to deal with the main aim of disposal systems, i.e.
to protect humans and the environment, now and in the future, by isolating the wastefrom man, the environment and the biosphere and by containing the radioactive and27

DRAFT REPORT FOR FOR CONSULTATION

1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081

other toxic substances in the waste to the largest extent possible. Optimisation ofprotection has to deal with the protection of workers and the public during the time ofoperation, as well as with the protection of future generations including possible
periods with no oversight, and safety has to be ensured by a passively functioning
disposal system.
(64) The stepwise decisional process for geological disposal facility development andimplementation constitutes the framework for the optimisation process. As a centralcomponent, optimisation has to cover all elements of the disposal system in an
integrative approach, i.e. site (incl. host formation), facility design, the application ofBest Available Techniques (BAT), waste package design, waste characteristics aswell as all relevant time periods.
(65) Optimisation of protection is a multi-facet endeavour, involving the disposal
facility developer, safety and environmental protection authorities, local communities
and other stakeholders and multiple decisions have to be taken. Therefore, it is notpossible to define a priori the path for a sound optimisation process for a geologicaldisposal facility, or the acceptance or success criteria for the end result of an
optimisation process.
(66) Socio-economical factors (including e.g. policy decisions and societal
acceptance issues) can constraint the optimisation process to various extents, e.g.
by limiting the available options (e.g. siting) and/or by defining additional conditions(e.g. retrievability). It is important that these constraints are identified in a mannertransparent to all involved stakeholders and that their safety implications are
generally and broadly understood. These factors must not force the optimisation
process to accept options that are questionable from a protection point of view.
(67) Although optimisation is a continuous effort, milestones will have to be defined in
the stepwise process, where all involved stakeholders can judge the result of the
optimisation process and indicate ways to improve various elements of the system.
(68) The process of optimisation will be considerably different for the pre-operational,
operational and post-operational phases. During the operational phase, the generalrecommendations for any large nuclear facility apply. Experience gained during theoperational phase can be factored into immediate or near term improvements,
reducing the exposure to both workers and the public from the emplacement work.
(69) Nearly all aspects of optimisation for the post-operational phase must occur prior
to waste emplacement, largely in the siting and design phase, with the plans to close
the facility being part of the design phase. Some further optimisation of the protectionthat will be provided during the post-operational phase is still possible during theoperational phase, for example as new materials or techniques may become
available. Experience gained during the closure of parts of the facility, e.g. sealing ofdisposal rooms, can lead to improvements of the plans of the disposal facility closure.
(70) During the post-operational phase, there is no active operation of the disposal
facility. The waste is emplaced and the protection of humans and the environment ismainly based on the passive isolation and containment capabilities of the disposal
28

DRAFT REPORT FOR FOR CONSULTATION

1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130

system. Hence decisions on optimisation in the post-operational phase can only
relate to the time and method of oversight of the closed disposal system. During thisphase optimisation of protection can best be achieved by maintaining oversight.
(71) Geological disposal facilities are sited, designed and implemented to provide forrobust long-time isolation and containment, resulting in potential impacts on humans
and the environment only in the very far future. Consequently, as explained earlier,the assessment of post-closure radiological impacts through the estimation ofeffective dose or risk to a reference person, given the increasing uncertainties withtime and the cautious assumptions to be made, can only provide an indication orillustration of the robustness of the system, rather than predictions of futureradiological consequences. As previously discussed, there comes a time in the
distant future beyond which any such calculated dose or risk values must be
considered for the sake of comparison of options rather than as absolute values.
(72) The elements guiding or directing the optimisation process should be those that
directly or indirectly determine the quality of the components of the facility as built,
operated and closed, where quality refers to the capacity of the components to fulfil
the safety functions of isolation and containment in a robust manner. The
assessment and judgment of the quality of system components essentially includes
elements of BAT as well as the concepts of good practice and sound engineeringand managerial principles. These elements complement and support radiologicaloptimisation when potential impacts in the far future have to be dealt with.
(73) The judgment of the quality of the system design developed or implemented has
to be made, and critically reviewed when needed, in a well-structured andtransparent process, with the involvement of all relevant stakeholders. At the heart ofthis process is the interaction, transparent for all other stakeholders, between thedeveloper and the safety authorities.
(74) When dealing with safety in the more distant future, optimisation can becomplemented and supported by applying the concept of BAT on the various levelsof the disposal system, through:---the methodologies for identifying and selecting (a) host rock(s), zones andsites, and the methodological and scientific program of host rock and sitecharacterization in order to assess its containment and isolation capacities
now and in the distant future;
the development of the system design, including the choices of materials andtechnologies, and the way they will contribute, individually and together, to themain aim of isolation and containment, taking due account of thecharacteristics of the host rock;the integration of waste, site and design characteristics within one disposal
system and the iterative assessment of the isolation and containment
capacities of the system as a whole;the use of sound managerial and engineering methods and practices duringsystem construction, operation and closure, within an integrated management
system.

29

DRAFT REPORT FOR FOR CONSULTATION

1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179

(75) Optimisation on the basis of radiological criteria (effective dose and risk) is an
important part of the optimisation of the design and implementation process of thedisposal facility at specific “windows” and for specific aspects of the disposal facility,e.g. when operational safety is assessed during the design development steps andduring preparation and implementation of operational procedures and activities.
(76) The way the various elements of a disposal system can be optimized in an
integrative manner during system development varies to a large extent. First of all
stepwise optimisation decisions have to be taken mostly in a chronological order: e.g.
the decisions on the choice of a host rock and on one or a limited number of sites areoften prior to decisions on a detailed design. For the selection of a host rock and asite, a balance has to be struck between technical criteria related to the safety of adisposal system (long-term stability, barrier for radionuclide migration, absence orpresence of natural resources in the vicinity, …) and the requirement of local or
supra-local societal acceptance. Favourable host rocks and sites can in a first step
be identified on the basis of broadly defined “required qualities”, taking due accountof the isolation and containment function(s) of the natural barriers and the naturalenvironment in the disposal system.
(77) If several suitable host rocks or sites can be identified and evaluated thedecision in favour of one specific host rock or site will always be a multi-factor
decision, based on both qualitative and quantitative judgments. Radiological criteria(e.g. calculated effective dose) are often of limited value for this multi-factor decision,
due to (1) the increasing uncertainties for longer assessment timescales, and (2) the
observation that often calculated radiological impacts are so low that they do notconstitute a discriminating factor for the choice of a host rock or site.
(78) The assessment of the robustness of the disposal facility can contribute tosystem optimisation, because it provides insight, quantitative or qualitative, in theperformance of the disposal facility and its components, in the relative contributionsof the various components to the overall system. So, the value of such anassessment for the optimisation process is mainly through the insights it provides on
the relative contributions of the various components to the overall system objective of
isolation and containment, and how these contributions can be affected by disturbing
events and processes or by remaining uncertainties. The indicative nature ofcalculated effective dose and risk in the very far future reduces their usefulness forthe optimisation process.
5. „Endpoint considerations“
5.1 The Representative Person(79) As general guidance, the Commission considers that its recommendations on
the estimation of exposures in Publication 101, part 1, apply. The Commission
therefore continues to recommend that for planned exposure situations exposures
should in general be assessed on the basis of the annual dose to the representative
person.
(80) During the operational phase, management of exposures to workers and the30

DRAFT REPORT FOR FOR CONSULTATION

1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228

public would be the same as for any other large nuclear facility. During the postoperational phase, due to the long time-scales under consideration, the habits andcharacteristics of the representative person, as well as those of the environment inwhich it is located, can only be based on a number of assumptions. In that case, anysuch representative person has to be hypothetical and stylized. The habits andcharacteristics assumed for the individual in a distant future should be chosen on thebasis of reasonably conservative and plausible assumptions, considering site or
region specific information as well as biological and physiological determinants ofhuman life. Moreover, in many cases, different scenarios, each associated withdifferent representative persons, may be considered for the long term and havedifferent probabilities of occurrence, although establishing discreet probabilities may
be problematic. Thus, the scenario leading to the highest dose may not be linked tothe highest risk. It is therefore important for the decision-maker to have a clear
presentation of the different scenarios and their associated probabilities ofoccurrence or at least with an appreciation of their corresponding probabilities.
(81) As stated in ICRP Publication 101, part 1, for the purpose of protection of the
public, the representative person corresponds to an individual receiving a dose that isrepresentative of the more highly exposed individuals in the population. Therefore, it
should be assumed that the hypothetical representative person is located at the timeand place of the maximum concentration of radionuclides in the biosphere. This is an
assumption since the environment may have evolved such that humans are nolonger inhabiting these areas in the far future.
(82) A representative person cannot be defined independently of the assumed
biosphere. Major changes may occur in the biosphere in the long-term due to theaction of natural forces in a similar manner to those occurring in the past. Human
actions may also affect the biosphere, but one can only speculate about humanbehaviour in the long-term. In the definition of the scenarios, consideration ofbiosphere changes should be limited to those due to natural forces. A representative
person and biosphere should be defined using either a site specific approach basedon site or region specific information or a stylized approach based on more general
habits and conditions; the use of stylized approaches will become more important for
longer time-scales.
(83) In the long term, if radionuclides are present in the environment, exposures of
the representative person are expected to occur during a whole lifetime. The
Commission recommends in its Publication 101, part 1, to use three age categories
for estimating annual dose to the representative person, for comparison with annual
dose or risk criteria. (Note that the annual dose from the intake of a radionuclide
already includes a component relating to the fact that the radionuclide will deliver adose in successive years, the length of time being determined by the biological halflife of the radionuclide in the body). These categories are 0-5 years (infant), 6-15
years (child), and 16-70 years (adult). Decisions can also be made by considering
doses or risks on a lifetime exposure instead on a per annum scale. For thecomparison of doses to individuals of current and future generations, however, it may
be necessary to calculate doses for different age groups for future exposures fromthe radioactive waste site or vice versa to calculate doses for a representative personof the current generation on the basis of lifetime exposure.
31

DRAFT REPORT FOR FOR CONSULTATION

1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272

5.2 Protection of the environment(84) Illustration that the environment is protected against harmful effects of releases
from facilities is an increasing requirement in national legislation and in relation to
many human activities including the management of long-lived waste. ICRP has
responded to this need as well as to a number of other requirements of ethical nature(as laid out in its Publication 91) by directly and specifically addressing environmental
protection in ICRP Publication 103 and by offering a methodology to address thisissue, as outlined in ICRP Publication 108.
(85) The ICRP approach considers the health of the environment (not the presenceof contamination or other factors that may affect the environment as a resource), withthe aim of “preventing or reducing the frequency of deleterious effects on fauna andflora to a level where they would have a negligible impact on the maintenance of
biological diversity, the conservation of species, or the health status of natural
habitats, communities and ecosystems” (ICRP Publication 103 para 30). The fullevaluation of environmental impact would normally be assessed through theEnvironmental Impact Assessment process and in the Environmental Impact
Statement, where effects will be considered within a broader context including suchfactors as inter alia, visual impact, chemotoxic impact, noise, land use and amenities.
(86) The default target for protection and protective actions could be the set ofReference Animals and Plants that have been described by ICRP and for which therelevant data sets have been derived (Publication 108). The use of Reference
Animals and Plants offers on one hand a challenge for waste management which is
at least similar to the challenges of demonstrating compliance with dose/risk
standards; but, on the other hand, also offers an additional line of argument andreasoning in building a safety case, using endpoints that are different from, but
complementary to, protection of human health. Consideration of environmental
protection, where appropriate, would thus broaden the basis for risk-informed
decision making and addressed issues that may have differing levels of importancefor different stakeholders.
(87) Over the long time frames that are considered in waste disposal, the biosphereis likely to change, and even change substantially. Such changes entail biosphere
evolution with time that is either natural, or enhanced or perturbed through humanaction. Contributing factors may be, e.g., climate change including glaciations cycles,
and land uplift or depression. Understanding different biospheres today andassessing impacts in such biospheres based on an approach involving Reference
Animals and Plants, may guide our understanding of future biosphere changes also
for the purpose of environmental protection.

32

DRAFT REPORT FOR FOR CONSULTATION

1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321

6. References
IAEA, 1997. Joint Convention on the Safety of Spent Fuel Management and on the
Safety of Radioactive Waste Management. INFCIRC/546, IAEA, 24 December 1997.
IAEA, 2009. Classification of Radioactive Waste. IAEA Safety Standard Series No.
GSG-1, IAEA, November 2009.
ICRP, 1977. Recommendations of the International Commission on RadiologicalProtection. ICRP Publication 26. Ann. ICRP 1 (3).
ICRP, 1985. Principles for the disposal of solid radioactive waste. ICRP Publication
46. Ann. ICRP 15 (4).
ICRP, 1991. 1990 Recommendations of the International Commission on
Radiological Protection. ICRP Publication 60. Ann. ICRP 21 (1–3).
ICRP, 1993. Protection from potential exposure: a conceptual framework. ICRP
Publication 64. Ann. ICRP 23 (1).
ICRP, 1997a. Protection from potential exposures: application to selected sources.
ICRP Publication 76. Ann. ICRP 27 (2).
ICRP, 1997b. Radiological protection policy for the disposal of radioactive waste.
ICRP Publication 77. Ann. ICRP 27 (Suppl).
ICRP, 1998. Protection recommendations as applied to the disposal of long-lived
solid radioactive waste. ICRP Publication 81. Ann. ICRP 28 (4).
ICRP, 1999. Protection of the public in situations of prolonged exposure. ICRP
Publication 82. Ann. ICRP 29 (1–2).
ICRP, 2003. A framework for assessing the impact of ionising
species. ICRP Publication 91. Ann. ICRP 33 (3).

on non-human

ICRP, 2006. Assessing dose of the representative person for the purpose ofprotection of the public and The optimisation of radiological protection: Broadening
the process. ICRP Publication 101. Ann. ICRP 36 (3).
ICRP, 2007a. The 2007 Recommendations of the International Commission on
Radiological Protection. ICRP Publication 103. Ann. ICRP 37 (2–4).
ICRP, 2007b. Scope of radiological protection control measures. ICRP Publication
104. Ann. ICRP 37 (4).
ICRP, 2008. Environmental Protection: the Concept and Use of Reference Animals
and Plants. ICRP Publication 108. Ann. ICRP 38 (4-6).
ICRP, 2009. Application of the Commission‟s recommendations for the protection of33

DRAFT REPORT FOR FOR CONSULTATION

1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342

people in emergency exposure situations. ICRP Publication 109. Ann. ICRP 39 (1).
ICRP, 2010. Application of the Commission‟s Recommendations to the Protection of
People Living in Long-term Contaminated Areas after a Nuclear Accident or a
Emergency. ICRP Publication 111. Ann. ICRP 39 (3).
OECD-NEA, 2007. Regulating the Long-term Safety of Geological Disposal Towards a Common Understanding of the Main Objectives and Bases of Safety
Criteria – OECD-NEA, Dec. 2007.
OECD-NEA, 2008. Moving Forward with Geological Disposal of Radioactive Waste –A Collective Statement by the NEA Radioactive Waste Management Committee –OECD/NEA, 2008.
OECD-NEA, 2010. Main Findings in the International Workshop “Towards
Transparent, Proportionate and Deliverable Regulation for Geological Disposal” Tokyo, Japan, 20-22 January 2009 – OECD-NEA, March 2010.
WHO, 2008. Guidelines for Drinking-water Quality. Third Edition, WHO, Geneva,
2008.

34

DRAFT REPORT FOR FOR CONSULTATION

1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391

Annex 1: The ICRP system of protection, focusing on aspects relevant to thegeological disposal of long-lived solid radioactive waste
The purpose of this annex is to summarize the key recommendations of ICRP
relevant to waste disposal.
In its Publication 103, the ICRP Recommendations evolve from the previous processbased protection approach using practices and interventions by moving to an
approach based on the exposure situation. They recognise planned, emergency, andexisting exposure situations, and apply the fundamental principles of justification andoptimisation of protection to all of these situations. They maintain the Commission‟scurrent individual dose limits for effective dose and equivalent dose from all regulated
sources in planned exposure situations. They reinforce the principle of optimisation ofprotection, which should be applicable in a similar way to all exposure situations,subject to the following restrictions on individual doses and risks; dose and risk
constraints for planned exposure situations, and reference levels for emergency andexisting exposure situations. The Recommendations also include an approach fordeveloping a framework to demonstrate radiological protection of the environment.
I. Principles of Protection
The three fundamental principles of protection areJustiﬁcation: Any decision that alters the exposure situation should
do more good than harm. This means that, by introducing a new source, byreducing existing exposure, or by reducing the risk of potential exposure, one
should achieve sufficient individual or societal beneﬁt to offset the detriment it
causes.
Waste management and disposal operations are an integral part of thepractice generating the waste. It is wrong to regard them as a free standing
practice that needs its own justification. The waste management and disposal
operations should therefore be included in the assessment of the justificationof the practice generating the waste (ICRP 77 §34). This assessment should
include considerations of different options for waste management and disposal
including the justification of these options. If the national waste disposal policy
has changed and the practice is continuing, it may be necessary to reassess
the justification of the practice. If the practice has ceased, the protection
strategy, rather than the practice, has to be considered for justification.
Optimisation of protection: the likelihood of incurring exposures, thenumber of people exposed, and the magnitude of their individual doses should
all be kept as low as reasonably achievable, taking into account economic andsocietal factors. This means that the level of protection should be the best
under the prevailing circumstances, maximising the margin of beneﬁt overharm. In order to avoid severely inequitable outcomes of this optimisation
procedure, there should be restrictions on the doses or risks to individuals
from a particular source.
Application of dose limits: The total dose to any individual from35

DRAFT REPORT FOR FOR CONSULTATION

1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440

regulated sources in planned exposure situations other than medical exposureof patients should not exceed the appropriate limits recommended by theCommission. Regulatory dose limits are determined by the regulatory
authority, taking account of international recommendations, and apply toworkers and to members of the public in planned exposure situations.
The role of optimisation
When optimising protection strategies, it is necessary to consider all aspects andprotective measures to reduce residual dose, questioning whether „the best has been
done in the prevailing circumstances, and if all that is reasonable has been done to
reduce doses‟ (ICRP Publication 103, Para. 217). This approach focuses efforts on
optimising protection in order that individual exposures, from all pathways, resulting
from the operation of a waste disposal facility (i.e. residual doses) are judged to be
acceptable in the context of the circumstances being planned for and the expectedresources required/allocated for protection. This approach implies the simultaneous
optimisation of all protective measures that are included in the protection strategy,
implemented if necessary in a stepwise fashion to address prevailing circumstances
appropriately.
All aspects of optimisation cannot be codified; rather, there should be a commitment
by all parties to the optimisation process. Where optimisation becomes a matter forthe regulatory authority, the focus should not be on specific outcomes for a particularsituation, but rather on processes, procedures, and judgements. An open dialogue
should be established between the authority and the operating management, and thesuccess of the optimisation process will depend strongly on the quality of this
dialogue.
Societal values usually influence the final decision on the level of radiologicalprotection. Therefore, while this report should be seen as providing decision-aiding
recommendations mainly based on scientific considerations on radiologicalprotection, the Commission‟s advice will be expected to serve as an input to a final(usually wider) decision-making process, which may include other societal concernsand ethical aspects, as well as considerations of transparency (ICRP Publication
101). This decision-making process may often include the participation of relevant
stakeholders rather than radiological protection specialists alone.
II. Types of exposures and of exposure situations
The Commission distinguishes between three categories of exposure: occupational,
public, and medical exposures of patients.
The Commission intends its Recommendations to be applied to all sources and toindividuals exposed to in the following three types of exposure situations which
address all conceivable circumstances (ICRP Publication 103, para.176).
Planned exposure situations are situations involving the deliberate
introduction and operation of sources; including decommissioning, disposalof radioactive waste and rehabilitation of the previously occupied land.
Planned exposure situations may give rise both to exposures that are
36

DRAFT REPORT FOR FOR CONSULTATION

1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489





anticipated to occur (normal exposures) and to exposures that are notanticipated to occur (potential exposures).
Emergency exposure situations are situations that may occur during theoperation of a planned situation, or from a malicious act, or from any otherunexpected situation, and require urgent action in order to avoid or reduce
undesirable consequences.
Existing exposure situations are exposure situations that already exist
when a decision on control has to be taken, including prolonged exposure
situations after emergencies.

It follows that what the Commission has previously called „practices‟ could be theorigin of planned, emergency, and existing exposure situations. The principles ofprotection for planned situations also apply to occupational exposure in connection
with existing and emergency exposure situations.
III. Dose concepts (effective dose, collective dose)
The main and primary uses of effective dose in radiological protection for both
occupational workers and the general public are (ICRP Publication 103, para. 153):
 prospective dose assessment for planning and optimisation of protection; and retrospective dose assessment for demonstrating compliance with dose limits,or for comparing with dose constraints or reference levels.
In practical radiological protection applications, effective dose is used for managing
the risks of stochastic effects in workers and the public.
The overall exposure, which is projected to occur as a result of the emergency
exposure situation, should no protective actions be employed, is called the projected
dose. The dose that would result when a protection strategy is implemented is called
the residual dose. In addition, each protective measure will avert a certain amount of
exposure. This is referred to as averted dose.
ICRP Publication 103, para. 159: For the purpose of optimisation of radiologicalprotection, predominantly in the context of occupational exposure, the Commission
has introduced collective dose quantities (ICRP Publication 26). These quantities
take account of the exposure of all individuals in a group over a given time period or
during a given operation executed by this group in designated areas. Collective
effective dose is not intended as a tool for epidemiological studies, and it isinappropriate to use it in risk projections.
IV. Dose limits, constraints and reference levels(B 174) In practice, limits, constraints, reference levels, and action levels are definedin terms of dose quantities in order to restrict the risks from exposure for both
occupational workers and the public. Since neither quantity can be directly
measured, they are assessed using other measurable quantities, models andcomputations. Depending on the situation considered (occupational or public
exposure), different procedures are applied.
Dose limit
37

DRAFT REPORT FOR FOR CONSULTATION

1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538

The value of the effective dose or the equivalent dose to individuals from planned
exposure situations that shall not be exceeded. Numerical values are given in Tab. 8(ICRP Publication 103).
Dose constraint
A prospective and source-related restriction on the individual dose from a source,which provides a basic level of protection for the most highly exposed individuals
from a source, and serves as an upper bound on the dose in optimisation ofprotection for that source. For occupational exposures, the dose constraint is a valueof individual dose used to limit the range of options considered in the process of
optimisation. For public exposure, the dose constraint is an upper bound on theannual doses that members of the public should receive from the planned operationof any controlled source. Numerical values are given in Tab. 8 (ICRP Publication
103).
Reference level
In emergency or existing exposure situations, the reference level represents the levelof dose or risk, above which it is judged to be inappropriate to plan to allow
exposures to occur, and below which optimisation of protection should be
implemented. The chosen value for a reference level will depend upon the prevailingcircumstances of the exposure under consideration. Numerical values are given in
Tab. 8 (ICRP Publication 103).
Derived consideration reference level
For the purpose of environmental protection, ICRP has in Publication 108 identified
Derived Consideration Reference Levels (DCRLs). These are „bands‟ ofenvironmental dose (expressed as absorbed dose) rates, spanning one order ofmagnitude, for the different Reference Animals and Plants, that “can be considered aband of dose rates within which there is likely to be some chance of deleterious
effects occurring to individuals of that type of Reference Animal or Plant....that, when
considered with other relevant information, can be used as a point of reference tooptimise the level of effort expended on environmental protection (Publication 108,
para. 195).
Potential exposure is an exposure that is not expected to be delivered with certainty
but that may result from an accident at a source or an event or sequence of events ofa probabilistic nature, including equipment failures and operating errors.
Risk constraint
A prospective and source-related restriction on the individual risk (in the sense ofprobability of detriment due to a potential exposure) from a source, which provides abasic level of protection for the individuals most at risk from a source and serves as
an upper bound on the individual risk in optimisation of protection for that source.
This risk is a function of the probability of an unintended event causing a dose, andthe probability of detriment due to that dose. Risk constraints correspond to dose
constraints but refer to potential exposures.
ICRP Publication 103, para. 268: Risk constraints, like dose constraints, are sourcerelated and in principle should equate to a similar health risk to that implied by the38

DRAFT REPORT FOR FOR CONSULTATION

1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587

corresponding dose constraints for the same source. However, there can be large
uncertainties in estimations of the probability of an unsafe situation and the resulting
dose. Thus, it will often be sufficient to use a generic value for a risk constraint. In thecase of workers, this could be based on generalisations about normal occupational
exposures, rather than on a more speciﬁc study of the particular operation. For
potential exposures of workers, the Commission continues to recommend a genericrisk constraint of 2 10-4 per year which is similar to the probability of fatal cancer
associated with an average occupational annual dose of 5 mSv (ICRP, Publication
76). For potential exposures of the public, the Commission continues to recommend
a risk constraint of 1 10-5 per year.
V. Protection of the environment.
The Commission acknowledges that, in contrast to human radiological protection, theobjectives of environmental protection are both complex and difficult to articulate.
The Commission does however subscribe to the global needs and efforts required tomaintain biological diversity, to ensure the conservation of species, and to protect thehealth and status of natural habitats, communities, and ecosystems. It also
recognises that these objectives may be met in different ways, that ionising may be
only a minor consideration – depending on the environmental exposure situation –and that a sense of proportion is necessary in trying to achieve them (ICRP
Publication 103, para. 361).
The Commission therefore believes that the development of a clearer framework is
required in order to assess the relationships between exposure and dose, andbetween dose and effect, and the consequences of such effects, for non-humanspecies, on a common scientific basis. This issue was first discussed in ICRP
Publication 91, and it was concluded that it was necessary to draw upon the lessons
learned from the development of the systematic framework for the protection ofhuman beings. This framework is based on an enormous range of knowledge that
the Commission attempts to convert into pragmatic advice that will be of value inmanaging different exposure situations, bearing in mind the wide range of errors,
uncertainties, and knowledge gaps of the various databases (ICRP Publication 103,
para. 364).
The Commission does not therefore propose to set any form of „dose limits‟ withrespect to environmental protection. However, by setting out data for some
Reference Animals and Plants, in a transparently derived way, and upon whichfurther action may be considered, the Commission offers practical advice as laid out
in Publication 108. The Commission will continue to develop this framework togather and interpret data in order to provide more comprehensive advice in the
future, particularly with regard to those aspects or features of different environmentsthat are likely to be of concern under different exposure situations (ICRP Publication
103, para. 370)
VI. Stakeholder involvement
Since the mid 90s, the involvement of stakeholders in decision making related toprotection issues has been recognised as a key process notably for favouring the39

DRAFT REPORT FOR FOR CONSULTATION

1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636

understanding of the protection measures, improving the protection, adapting themeasures to the local context and ensuring the sustainability of the protection. ICRP
Publication 82 (1999) is the first ICRP Publication mentioning explicitly stakeholder
involvement: “Many situations of prolonged exposure are integrated into the humanhabitat and the Commission anticipates that the decision-making process will include
the participation of relevant stakeholders, rather than radiological protection
specialists alone.” (para. 4).
Furthermore, in ICRP Publication 91 (2003) stakeholder involvement is introduced aspart of the “principles” for protecting the environment: “The principle of informed
consent, which emphasises the need for communication and public involvement,
starting at the planning stage and well before decisions are taken from which there is
no return. Such transparency of decision making should enable analysis andunderstanding of all stakeholder‟s arguments… » (Current environmental
management principles, para. 47).
In ICRP Publication 101 Part 1 (2006), dealing with Assessing Dose of theRepresentative Person for the Purpose of Protection of the Public, there is a firstelicitation of the advantages of engaging stakeholders: “In the case of defining
characteristics of the representative persons, stakeholder involvement can play animportant role… In particular, stakeholders can be helpful in determining thereasonableness, sustainability, and homogeneity of habit data. Collaboration withstakeholders can significantly improve the quality, understanding and acceptability ofcharacteristics of the representative person, and also strengthen support for theprocess and the results.” (Value of stakeholder input in characterising therepresentative person, § 102).
It is then reinforced in ICRP Publication 101 Part 2 (2006) as well as in ICRP
Publication 103 (2008) for the Optimisation of Radiological Protection: “The
involvement of stakeholders is a proven means to achieve incorporation of values
into the decision-making process, improvement of the substantive quality ofdecisions, resolution of conflicts among competing interests, building of sharedunderstanding with both workers and the public, and building trust in institutions.
Furthermore, involving all concerned parties reinforces the safety culture andintroduce the necessary flexibility in the management of the radiological risk that isneeded to achieve more effective and sustainable decisions.” (The optimisation
process, ICRP Publication 101 Part 2, para. 39).
More recently, stakeholder engagement processes were considered as key
components of the development of strategies in case of preparedness of emergency
situations and management of existing situations. (ICRP Publication 109 related to
the Application of the Commission‟s Recommendations for the Protection of People
in Emergency Exposure Situations and ICRP Publication 111 related to theApplication of the Commission‟s Recommendations to the Protection of People Living
in Long Term Contaminated Areas After a Nuclear Accident or a Radiological
Emergency).
These considerations fully apply to radioactive waste management. The Commission
recognises that the nature and extent of stakeholder involvement may vary between
40

DRAFT REPORT FOR FOR CONSULTATION

1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648

countries, but suggests that engagement with stakeholders is an importantcomponent to the justiﬁcation and optimisation of protection strategies in waste
disposal projects. During planning, it is essential that the plan is discussed, to theextent practicable, with relevant stakeholders, including other authorities and the
public. Otherwise, it will be difficult to implement the plan effectively during operation.
The overall protection strategy and its constituent individual protective measures
should have been worked through with all those potentially exposed or affected.
In addition, because of the long time scale at stake, it is also necessary to consider
the role of stakeholders to deal with intergenerational transmission of knowledge andmemory of installations and protection strategies.

41

DRAFT REPORT FOR FOR CONSULTATION

1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697

Annex 2 ICRP use of “potential exposure“
ICRP has frequently used the term „potential exposure“ in its publications:“…..The 1955 Conference on the Peaceful Uses of Atomic Energy had aroused
great interest in the development of atomic power plants throughout the world. In
time this would greatly increase the number of persons occupationally exposed
and would also bring about actual or potential exposure of other persons andthe population as a whole.” (ICRP Publications 1, 3, 4).
Further uses of the term „potential exposure“ can be found in ICRP
recommendations related to various fields of radiological protection (Publ. 10, 36, 37,
40, 42, 43, 54, 57).
The first comprehensive discussion of the nature and application of the term
„potential exposure“ is given in ICRP Publ. 60 and 64 (Protection from potential
exposure):“(2) exposure which might result from the introduction of a practice is also divided
into two broad categories: normal exposure and potential exposure. Normal
exposure is that exposure which can reasonably be expected to occur, i.e., theexposure is predicted to occur with a probability of one or near one, independentof the time when the exposure occurs. It includes both exposure from operations
conducted as planned as well as unintended high probability, low consequence
events. These events are nearly certain to occur during operations but result in
doses that are within prescribed limits. Potential exposure is exposure that,while not certain to occur, can be anticipated as a result of introducing or
modifying a practice and to which a probability of occurrence can be assigned.
Such exposure involves consideration of risk which falls outside the generalboundaries considered for normal exposure. The occurrence of potential eventsand the chances that such events will result in a dose to an individual or group ofindividuals, when combined with the probability of effects from the expected
resulting dose, can be presented as an a priori probability of harm. The initialconsideration of potential exposures, therefore, should form part of the system ofprotection applied to practices, but it should be recognised that the exposures, if
they occur, may lead to intervention (ICRP, 1991).”(4) Potential exposure situations may arise from the introduction of most, if not all,practices and involve a large variety of potential consequences. ….. There arealso potential exposure situations, such as those associated with radioactive
waste disposal, which can arise in the far distant future where consequences
become much more difficult to predict. Although safety for this wide spectrum ofsituations should be governed by coherent and consistent principles, the level ofeffort required to implement the principles and the formulation of acceptancecriteria will differ substantially depending on the complexity of the practice,sophistication of the engineering safety systems and the possible consequences.
(5) In practical application, a system of protection against potential exposure must
apply fundamental safety principles developed for complex technical systems…...
The report is intended to show how the fundamental safety principles can beapplied to all potential exposure situations….. Although the methods ofapplication of those principles may be less complex for a less complex source of ,a conscientious application of the safety principles to the design and operation of42

DRAFT REPORT FOR FOR CONSULTATION

1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730

1731
1732
1733
1734
1735
1736
1737
1738

sources appears appropriate to reduce the risk of accidental exposure in manyindustrial and medical practices.
(11) In order to maintain a strict coherence in the treatment of actual and potential
exposures, it is necessary to extend the concept of detriment to include theprobability of occurrence of the situation giving rise to the detriment…. emphasis
has to be placed on one part of detriment - the probability of an attributable death.
However, nominal probability coefficients for stochastic effects that include nonfatal cancer and severe hereditary effects can be used in considering detriment to
individuals from potential exposure. It must also be recognised that theuncertainties in estimating the probability of occurrence will usually be muchgreater than the uncertainties in estimating the probability of the consequences,
should the dose occur.
(33) The system of radiological protection recommended by the Commission forproposed and continuing practices is based on the following general principles.
(b) In relation to any particular source within a practice, the magnitude ofindividual doses, the number of people exposed and the likelihood of incurringexposures where these are not certain to be received should all be kept as low asreasonably achievable, economic and social factors being taken into account.
This procedure should be constrained by restrictions on the doses to individuals(dose constraints), or the risks to individuals in the case of potential
exposures (risk constraints), so as to limit the inequity likely to result from theinherent economic and social judgments. (The optimisation of protection)(61) Limits are used in safety to control the risk to individuals from all stipulated
sources of exposure. However, in order to establish requirements to constrain
exposure to individuals from a particular source, the Commission has
recommended the use of constraints in the process of optimisation, which aresource related and should be established in a manner such that the sum of therisks from all relevant sources does not exceed the individual limit. For thetreatment of potential exposure, the Commission recommends that limits ofrisk be of the same order of magnitude as the health risk implied by thedose limits for normal exposures. However, the dose limits themselves are
not applicable to potential exposure situations.

The guidance provided in Publication 64 has been used and further developed in
ICRP Publications 73, 77, 81, 82, 92, 94 and 101.
Publication 103 confirms the basic principles by the following statements:
Para. 176: Planned exposure situations are situations involving the deliberate
introduction and operation of sources. Planned exposure situations may give rise43

DRAFT REPORT FOR FOR CONSULTATION

1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787

both to exposures that are anticipated to occur (normal exposures) and toexposures that are not anticipated to occur (potential exposures).
Para. 205: The Commission recommends that, when activities involving an
increased or decreased level of exposure, or a risk of potential exposure, arebeing considered, the expected change in detriment should be explicitly includedin the decision-making process.
Para 214: Optimisation is always aimed at achieving the best level of protection
under the prevailing circumstances through an ongoing, iterative process thatinvolves: evaluation of the exposure situation, including any potential
exposures…
Para 229: In Table 4 the different types of dose restrictions used in theCommission’s system of protection (limits, constraints, reference levels) are
shown in relation to type of exposure situation and category of exposure. In
planned exposure situations, there are also risk constraints in order to takeaccount of potential exposures.
Para 254: All categories of exposure can occur in planned exposure situations,
i.e., occupational exposure, public exposure, and medical exposure of patients…..
The design and development of planned situations should have proper regard forpotential exposures that may result from deviations from normal operating
conditions. Due attention should be paid to the assessment of potential
exposures and to the related issue of the safety and security of sources.
Chapter 6.1.3 provides further details.
Para 265 states: “Events in which the potential exposures could occur far in the
future, and the doses be delivered over long time periods, e.g., in the case ofsolid waste disposal in deep repositories: Considerable uncertainties surroundexposures taking place in the far future. Thus dose estimates should not be
regarded as measures of health detriment beyond times of around several
hundreds of years into the future. Rather, they represent indicators of theprotection afforded by the disposal system. The Commission has given speciﬁc
guidance for the disposal of long-lived solid radioactive waste in Publication 81(ICRP, 1998b). This guidance remains valid.”
Para 267: The principles of constructing and analysing scenarios are well known
and are often used in engineering. Their application was discussed in Publication
76 (ICRP, 1997b). Decisions on the acceptability of potential exposures shouldtake account of both the probability of occurrence of the exposure and its
magnitude. In some circumstances, decisions can be made by separate
consideration of these two factors. In other circumstances, it is useful to consider
the individual probability of -related death, rather than the eﬀective dose (ICRP,
1997b). For this purpose, the probability is deﬁned as the product of theprobability of incurring the dose in a year and the lifetime probability of -related
death from the dose conditional on the dose being incurred. The resulting
probability can then be compared with a risk constraint. If the probability is lower
than the risk constraint, it may be tolerated. Both of these approaches are
discussed in the Commission’s Recommendations for the disposal of long-lived
solid radioactive waste in Publication 81 (ICRP, 1998b).
Para 268: Risk constraints, like dose constraints, are source-related and inprinciple should equate to a similar health risk to that implied by thecorresponding dose constraints for the same source. However, there can be large
uncertainties in estimations of the probability of an unsafe situation and the44

DRAFT REPORT FOR FOR CONSULTATION

1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810

resulting dose. Thus, it will often be suﬃcient to use a generic value for a risk
constraint. In the case of workers, this could be based on generalisations aboutnormal occupational exposures, rather than on a more speciﬁc study of theparticular operation. Where the Commission’s system of dose limitation has been
applied and protection is optimised, annual occupational eﬀective doses to an
average individual may be as high as about 5 mSv in certain selected types ofoperation (UNSCEAR, 2000). For potential exposures of workers, theCommission therefore continues to recommend a generic risk constraint of 2 104
per year which is similar to the probability of fatal cancer associated with anaverage occupational annual dose of 5 mSv (ICRP, 1997b). For potential
exposures of the public, the Commission continues to recommend a risk
constraint of 1 10-5 per year.
Both dose and risk constraints should be applied in planned exposure situations.
For the specific situation of waste disposal dose constraints can be used forcomparison of options for normal releases, referred as “desing-basis evolution” ofthe depository facility. Events with lower probabilities than the desing-basis
evolution should be treated as potential exposures and would require theapplication of relevant risk constraints. Risk constraints will be applied either in an
aggregated or a disaggregated way.

45

DRAFT REPORT FOR FOR CONSULTATION

1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859

Annex 3 Technical and management principles and requirements
Ref.: ICRP 101 section 6.6.4, §315, 316 ff
The general implementation of the Commission‟s recommendations on the disposalof radioactive waste requires that organizational and managerial structures andprocesses are put into place, and that technical principles are applied. Organizational
structures and processes can largely differ from country to country, but should bebased on the principles laid down by the IAEA in its Fundamental Safety Principles.
The Commission recommends that management principles and requirements should
be applied to the disposal system development and implementation process toenhance the confidence that the protection of humans and the environment will beensured for as long as needed.
Management systems play an important role “to improve the safety performance ofthe organization through the planning, control and supervision of safety related
activities in normal, transient and emergency situations” and “to foster and support
strong safety culture through the development and reinforcement of good attitudes
and behaviour in individuals and teams so as to allow them to carry out their taskssafely” (IAEA GS-R-3).
The general requirements for establishing, implementing, assessing and continually
improving a management system have been formulated by IAEA, and specificrecommendations for the management system for the disposal of radioactive waste
in IAEA Safety Standards publication GS-G-3.4.
A management system designed to fulfill the international IAEA requirements
integrates safety, health, environmental, security, quality and economic elements,
with safety being the fundamental principle upon which the management system isbased. “The main aim of the management system shall be to achieve and enhancesafety by:-bringing together in a coherent manner all the requirements for managing theorganization;
describing the planned and systematic actions necessary to provide adequate
confidence that all these requirements are satisfied;ensuring that health, environmental, security, quality and economical
requirements are not considered separately from safety requirements, to help
preclude their possible negative impact on safety.” (IAEA GSG-3.4)

Maintaining and further developing knowledge, competences and skills for the
disposal of radioactive waste, as an essential element to ensure high levels of safety,
should be based on a combination of scientific research and technologicaldevelopment, insights gained from successive safety cases, learning throughoperational experience and technical cooperation between all actors. Independent
reviews, transparency and accessibility of information, and openness to stakeholder
participation are also important contributors for ensuring high levels of safety.

46

DRAFT REPORT FOR FOR CONSULTATION

1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875

A key technical principle for developing disposal systems and assessing their safety
is the concept of defence in depth which provides for successive passive safetymeasures, enhancing the confidence that the disposal system is robust and has anadequate margin of safety. The defence in depth concept as applied to disposal
systems imposes that safety is provided by means of the various components of thesystem contributing to fulfilling the main safety functions in different ways overdifferent timescales. The performance of the various components contributing tofulfilling the main safety functions has to be achieved by diverse physical andchemical processes, such that the overall performance of the system will not be
unduly dependent on a single component or function. The main safety objective of
the siting (a.o. selecting the natural barrier system and its environment) anddesigning (a.o. developing the man-made barrier system, taking due account of thesite characteristics) of a disposal system is to ensure that post-closure safety will be
provided by means of multiple safety functions and that even if a component orsafety feature does not perform fully as expected, a sufficient margin of safety willremain.

47